REPORT ON THE NUDIBRANCHIATA. 
51 
(PL XI. fig. 7, a, a) and the first lateral tooth (fig. 7, b,b) closely resemble those of other 
species of Mcirionia. All the (other) lateral plates (figs. 8-11), with the exception perhaps 
of the outermost ones, are covered on their outer edge with fine oblique striations, and 
the outer margin of the recurved extremity (fig. 12) is very finely serrated ; sometimes a 
similar striation is seen on the inside (fig. 10). The outer teeth (fig. 11) have the normal 
form. There w T ere present also (PL XI. fig. 8) a number of irregularly formed teeth. 
The salivary glands resemble those of other Tritonice ; they are wdiitish in colour 
and measure about 7 mm. in length and 2 '5 mm. in breadth ; the efferent duct is about 
3 mm. long. — The oesophagus is like that of other Tritonice. The first stomach is 
spherical, with a diameter of 5 '5 mm. ; the second short and cylindrical, with a length of 
about 1 '5 mm. Chitinous 'plates are developed in the second stomach, and are visible 
through its walls ; they are pale yellow in colour and variable in form; they were 
present to the number of sixty ; a larger plate frequently alternated with one, two, or 
three smaller plates ; the length of the larger plates was about 1T3 mm., and the height 
'6 mm. ; two of the plates were considerably larger than the rest (fig. 13). The intestine 
passes over the succenturiate liver; it is 14 mm. long by 2-1 mm. in diameter; a thick 
fold was developed on its inner wall, ending in a freely projecting extremity at about 
the end of the first half. The whole digestive tract, from the mouth to the anus, was 
filled with animal debris, apparently of Alcyonarians. 
The liver is of the usual form, conical ; its length is about 19 mm., and the breadth 
of the anterior portion about 7 mm., the colour is yellowish-white with a faint tinge of 
green. The succenturiate liver lies beneath the intestine ; it is about 5 mm. broad, 3 mm. 
in height, and nearly 3 mm. in length ; the colour is greyish-brown ; the internal cavity 
is small, and opens by a distinct duct into the hinder portion of the first stomach. 
The renal syrinx opens into the anterior portion of the pericardium on the right side ; 
its shape is oval, with very strongly developed interior folds; the length is about 1*5 
mm. 
The hermaphrodite gland forms a thick whitish layer over the yellow liver ; its 
structure was perfectly typical, in the lobes zoosperms and large oogene cells were found. 
The anterior genital mass forms an oblong somewhat compressed body of about 9 mm. 
in length, 6 mm. in height, and 5 ’5 mm. in breadth ; the position of the different portions 
of the genital mass was normal. The ampulla of the hermaphrodite duct is largely deve- 
loped and whitish in colour; the ductus ejacidatorius (fig. 14, d) is very long, and 
forms a coil at the base of the penis, which when unrolled has a length of 2 ‘5 cm. The 
penis (fig. 14, e, 15) is about 4 mm. long, and projects freely ; it is elongated and conical 
in form, and has the usual structure. The spermatheca (fig. 14, a) is spherical, of about 
4 mm. diameter ; the efferent duct (fig. 14, b) is about double the length of the sac 
itself; the inferior half is dilated into a vagina (fig. 14, c) ; the mucous gland is whitish, 
the albuminiparous gland yellowish in colour. 
